Trikepilot Social

Featuring Bob Martens

Mark: "We’re going to discuss
the topic of go arounds. And this is a topic so basic, so
fundamental. Why should we focus additional attention on the
subject of go arounds?"

Bob: "Mark, I’ve always been
a big advocate of the go around. I refer to it the most under
utilized maneuver in aviation! Think about it. When was the last
time you did an intentional go around without being required to?
I’ll bet it’s been a while!

Now, think about how many of
our awful landings might have been avoided had we exercised the
good judgment to do a go around.

When I queried the NTSB data
base to check out go-around accidents, there were over 1300
go-around accidents in the data base! That’s a lot of accidents.
Clearly we have some work to do in this area."

Mark: "Why do we have so many
go-around accidents, Bob?"

Bob: "While the go around is
certainly not an inherently difficult maneuver, the fact that it
is most often accomplished in close proximity to the ground cuts
into our margin of error. Add to that the fact that the pilot is
probably experiencing at least some degree of stress associated
with the reason for the go around, and we start to understand the
problem.

Now, factor in that the pilot
has probably not done this maneuver in months, and we are now
looking at a very serious problem. How can you expect to be good
a something that you don’t practice regularly? Simply stated, you
can’t!

The challenge of go arounds
is that they must be performed instinctively, without hesitation,
with precision. Far too many pilots are just not up to that
challenge!"

Mark: "Bob, why is it that
pilots fail to integrate go arounds into their training
regimen?"

Bob: "Well Mark, first, and
foremost, not enough pilots have a training regimen. I challenge
all pilots to look into their log books and validate just how
little time we spend on training. We all need to get back to
basics, working hard on take offs and landings, heading to the
practice area for stalls, steep turns and slow flight drills, and
practicing emergency procedures. Integrated into this training
must be go-around practice.

Any time we find ourselves
out of sync with our airplane, go around and catch up! Far too
often we find ourselves frantically chasing our airplane, hoping
to catch up and make all the corrections before the airplane
lands. That’s a dumb way to fly. Flying is like playing chess. We
should be always looking several moves ahead, not playing from
behind.

The go around is our tool to
do just that. Far too many pilots perceive the go around as a
negative procedure after a mistake. That is wrong! The go around
demonstrates excellent judgment and has no down side! By
practicing it and integrating it into our flying, we will be real
good at go arounds and not hesitate to perform one at any
time."

I've been extremely excited to see how many quality video producers
have "blossomed" here at TPSocial... awesome!

When I started this site back in 2001, there was no one publishing
any video from trikes (at all)... and I was happy to put up
postage-stamp sized low res vids.

Fast forward to 2012, and we now have HD resolution, and
studio-quality production levels... all being done by passionate
individuals with no formal training. WOW!

After trying some new things last year to expand our community
offerings, it has become clear that the number-one most used
feature on this site is the video hosting and commenting. As such,
I'm going to "re-boot" the Trikepilot Pro side of the site in
January by creating a "Featured Producer" section.

This new section will be for site members who have previously
posted videos that demonstrate an incredible sense of style and
production value. Once someone is invited to be a "producer" of
videos on the pro-side, their videos will be featured in this new
section and receive the voting of the community.

It is not my intention to be exclusionary, and no one will ever be
prohibited from posting to TPSocial. Rather it is a way to focus
the spotlight, and give some special attention, to those who
demonstrate that they are really crazy-wild over making awesome
videos. For everyone else, it is a way to have a more "cinematic"
experience, with a curated menu of "top-notch" videos from which to
view (if you so choose).

Explanation:Training and
proficiency underlie avi­ation safety. Recurrent training is a major
component of flight safety. Such training includes both
air and ground training. Each contributes significantly
to flight safety and neither can substitute for the
other. Training
sufficient to promote flight safety may well exceed what is
required by law.

qFollow
and periodically review programs of study or training exercises
to improve profici­ency. Adhere to a training plan that
will yield new ratings, certificates, and endorsements—or at the
very least, greater flight proficiency.

AIRCRAFT HARDWAREWhat You Need To Know

By Ron
Alexander

The quality of our workmanship in
building an airplane is very important. We all take the needed
time and spend the necessary money to ensure we have a high
quality airplane. We want it to not only look attractive, but
also to be safe. But what about the materials that hold the
airplane together the aircraft hardware? Do we try to cut
expenses by using questionable bolts or used nuts? Is it really
necessary to spend money on high quality aircraft hardware?
Absolutely! The hardware used to assemble your
airplane should be nothing but the best. Why take the time to
build a perfect wing only to attach it to the fuselage with used
hardware. It makes no sense. To quote the Airframe and
Powerplant Mechanics General Handbook . . . "The importance
of aircraft hardware is often overlooked because of its small
size; however, the safe and efficient operation of any aircraft
is greatly dependent upon the correct selection and use of
aircraft hardware." Very well stated. The same book also provides
us with a very good definition of aircraft hardware. "Aircraft
hardware is the term used to describe the various types of
fasteners and miscellaneous small items used in the manufacture
and repair of aircraft."

The subject of aircraft hardware
can certainly be confusing. Thousands upon thousands of small
items are used on a typical airplane. What does the custom
aircraft builder really need to know about hardware? Where do you
find the information? What reference is really the end authority
on proper installation? What do all of those AN numbers mean and
do I have to know them? What types of hardware should I really
learn more about in order to build my own airplane?

These questions will be answered
in this series of articles on aircraft hardware. I hope to
eliminate some confusion over what type of hardware to use and
how to properly install it. To begin our discussion, it is
absolutely imperative that you use nothing but aircraft grade
hardware. Commercial grade hardware found in hardware or
automotive stores is legal to use on an experimental airplane
butshould not be considered for
evena moment. Why? Let's look at bolts
as an example. Common steel bolts purchased from a hardware store
are made of low carbon steel that has a low tensile strength
usually in the neighborhood of 50,000 to 60,000 psi. They also
bend easily and have little corrosion protection. In contrast,
aircraft bolts are made from corrosion resistant steel and are
heat treated to a strength in excess of 125,000 psi. The same
comparison applies to most hardware items. So, use only
aircraft quality hardware on your airplane. Save the
other hardware for your tractor.

If aircraft hardware is special,
then there must be a standard against which it should be measured
and manufactured. That standard was actually developed prior to
World War 11, but became more definitive during that war. Each
branch of the military originally had its own standard for
hardware. As time went on these standards were consolidated and
thus the term AN which means Air Force-Navy (some prefer the
older term Army-Navy). Later the standards were termed MS which
means Military Standard and NAS which means National Aerospace
Standards. Thus, the common terms AN, MS and NAS. Together they
present a universally accepted method of identification and
standards for aircraft hardware. All fasteners are identified
with a specification number and a series of letters and dashes
identifying their size, type of material, etc. This system
presents a relatively simple method of identifying and cataloging
the thousands and thousands of pieces of hardware. Several pieces
of hardware will have both an AN number and an MS number that are
used interchangeably to identify the exact same piece. A cross
reference exists that compares these two numbers. So in the end,
you are able to read your plans or assembly manual and identify,
by number and letter, each piece of hardware on your airplane.
You can then obtain that piece and properly install it in the
right place. Imagine trying to do that without a system of
numbers. The specifications for each piece of hardware also
define the strength, tolerance, dimensions, and finish that is
applied. If you would like further information on this numbering
system, you can contact the National Standards Association in
Washington, DC.
Out of all the thousands of hardware pieces manufactured, which
ones are important to the custom aircraft builder? The following
types and categories of hardware will be discussed:

Bolts

Nuts

Washers

Screws

Cotter pins and safety
wire

Rivets

Turnlock fasteners

Miscellaneous items such as 0-rings,
crush washers, etc.

Control cable hardware

Fluid lines and fittings

Electrical wiring and
connectors

Where do you find information
concerning aircraft hardware? Your aircraft plans or assembly
manual should provide you with a general overview of hardware
used on your project. Use the hardware the aircraft designer or
kit manufacturer recommends. Do not substitute with your own
ideas. This can be dangerous. The manufacturer has tested the
design and its safety is dependent upon the proper pieces of
hardware. FAA Advisory Circular 43-13-IA is an excellent
reference source. The AirframeMechanics General
Handbook also has a very good section on the selection and
use of hardware. These two books are considered the primary
authority on the proper use of hardware. In addition, I would
recommend two other small reference books: the Standard
Aircraft Handbook and the Aviation Mechanic
Handbook. Both of these provide a good reference source. The
Aircraft Spruce & Specialty catalog also contains good
reference material on hardware. If you have any doubts about the
quality of the aircraft hardware you are purchasing, request a
copy of the manufacturer's specifications. These specifications
along with a specific manufacturer's lot number should be
available.

BOLTS

Bolts are used in aircraft
construction in areas where high strength is needed. Where this
strength is not necessary screws are substituted. Aircraft
quality bolts are made from alloy steel, stainless or corrosion
resistant steel, aluminum alloys and titanium. Within our
industry the first two are the most common. Aircraft bolts will
always have a marking on their head. If you see no markings at
all on the head of a bolt, do not use it. It is probably a
commercial grade bolt. The markings on bolts vary according to
the manufacturer. You should see an "X" or an asterisk along with
a name, etc. If you purchase a corrosion resistant (stainless
steel) bolt, the head of that bolt should have one raised dash.
An aluminum bolt will have two raised dashes on its head.
Aluminum bolts have limited use. They should not be used in
tension applications or where they will be continuously removed
for maintenance or inspection. A chart of typical bolt heads is
presented in Figure 1. NAS bolts have a higher tensile strength
(usually about 160,000 psi) and can be identified by a cupped out
head. Close tolerance bolts are machined more accurately than
general purpose bolts and they are used in applications requiring
a very tight fit. Close tolerance bolts can be either AN or NAS
and typically have a head marking consisting of a raised or
recessed triangle.

The standard bolts used in
aircraft construction are AN3 through AN20. Each bolt typically
has a hexagon shaped head and a shank that fits into the hole.
The shank is threaded on the end and the unthreaded
portion of the bolt is termed the grip. The diameter of
a bolt is the width of the grip. The shank of a bolt will be
either drilled to accept a cotter pin or undrilled. Another
option is to purchase a bolt that has the head drilled for the
purpose of accepting safety wire. Clevis bolts are manufactured
with a slotted head and are used for control cable applications.
The size, material, etc. of a bolt is identified by an AN number.
A breakdown of a typical bolt AN number follows:

AN4-8A

AN means the bolt is manufactured
according to Air Force-Navy specs.

4 identifies the diameter of the bolt
shank in 1/16" increments

8 identifies the length of the shank
in 1/8" increments

A means the shank of the bolt is
undrilled (no letter here means a drilled
shank)

So, this particular bolt is a 1/4
inch diameter AN bolt that is 1/2 inch long measured from just
under the head to the tip of the shank. The bolt also has an
undrilled shank which means it cannot accept a cotter pin. Also,
bolt length may vary by +1/32" to -1/64". If the letter "C"
follows the AN designation (ANC) that identifies a stainless
steel bolt. The letter "H" after AN (ANH) identifies a drilled
head bolt.

In constructing you airplane, you
will not encounter many bolts larger than an AN8 (1/2 inch
diameter). To add a bit more confusion, if the dash number
defining the length of the bolt has two digits, the first digit
is the length in whole inches and the second number the length in
additional 1/8" increments. In other words, an AN514 bolt would
be I- 1/2 inches long.

Now that you are totally confused
let me recommend a hand tool to simplify bolt selection and
sizing. An AN bolt gauge is available that will assist you in
identifying a bolt (click on the above link to Figure 2).

If you need to determine the
proper size of a bolt, the length must be sufficient to ensure no
more than one thread will be inside the bolt hole. This is the
grip length of the bolt and it is measured from the
underneath portion of the head to the beginning of the threads
(see Figure 3 below). The grip length should be equal to the
material thickness that is being held by the bolt or slightly
longer. A washer may be used if the bolt is slightly longer. A
piece of welding rod or safety wire can be used to measure the
length of the hole. In his book titled SportplaneConstruction Techniques, Tony Bingelis shows a simple
tool that can be made for this purpose.
It is important that you do not "over tighten" or "under tighten"
a bolt or the nut attached to a bolt. Under torque or under
tightening results in excessive wear of the hardware as well as
the parts being held. Over tightening may cause too much stress
on the bolt or nut. The best way to avoid this is to use a torque
wrench. AC43-13 presents a table of torque values for nuts and
bolts. It shows fine thread and coarse thread series with a
minimum and maximum torque limit in inch pounds. I recommend
using a torque wrench whenever possible, at least until you get
an idea as to the amount of force required. Of course, critical
installations should definitely be torqued to proper values. A
torque wrench is not that expensive and will be a worthwhile
investment for a custom builder.

Basics of Bolt
Installation

Certain accepted practices
prevail concerning the installation of hardware. A few of these
regarding bolt installation follow:

In determining proper bolt length - no
more than one thread should be hidden inside the bolt
hole.

Whenever possible, bolts should be
installed pointing aft and to the center of an
airplane.

Use a torque wrench whenever possible
and determine torque values based on the size of
bolt.

Be sure bolt and nut threads are clean
and dry.

Use smooth, even pulls when
tightening.

Tighten the nut first - whenever
possible.

A typical installation includes a bolt,
one washer and a nut.

If the bolt is too long, a maximum of
three washers may be used.

If more than three threads are
protruding from the nut, the bolt may be too long and could be
bottoming out on the shank.

Use undrilled bolts with fiber lock
nuts. If you use a drilled bolt and fiber nut combination, be
sure no burrs exist on the drilled hole that will cut the
fiber.

If the bolt does not fit snugly consider
the use of a close tolerance bolt.

Don't make a practice of cutting off a
bolt that is too long to fit a hole. That can often weaken the
bolt and allow corrosion in the area that is cut.

AIRCRAFT
NUTS

Aircraft nuts usually have no
identification on them but they are made from the same material
as bolts. Due to the vibration of aircraft, nuts must have some
form of a locking device to keep them in place. The most common
ways of locking are cotter pins used in castle nuts, fiber
inserts, lockwashers, and safety wire. The aircraft nuts you will
most likely encounter are castle nuts, self-locking nuts, and
plain nuts. Wing nuts and anchor nuts are also used.

Castle
Nuts

AN310 and AN320 castle nuts are
the most commonly used (see Figure 4). Castle nuts are fabricated
from steel and are cadmium plated. Corrosion resistant castle
nuts are also manufactured (AN310C and AC320C - remember, when
you encounter a "C" it will designate stainless). Castle nuts are
used with drilled shank bolts, clevis bolts and eye bolts. The
slots in the nut accommodate a cotter pin for safetying purposes.
The thinner AN320 castellated shear nut has half the tensile
strength of the AN310 and is used with clevis bolts which are
subject to shear stress only. The dash number following the AN310
or AN320 indicates the size bolt that the nut fits. In other
words, an AN310-4 would fit a 1/4 inch
bolt.

Self-Locking Nuts

Self-locking nuts, as the name
implies, do not need a locking device. The most common method of
locking is derived from a fiber insert. This insert has a smaller
diameter than the nut itself so that when a bolt enters the nut
it taps into the fiber insert producing a locking action. This
fiber insert is temperature limited to 250-deg. F. The
designation of these nuts is AN365 and AN364. This brings us to
an example of a cross-reference MS number. An AN365 is also
termed MS20365 with the AN364 being MS20364. Both of these nuts
are available in stainless. The AN364 is a shear nut not to be
used in tension.

An all metal locking nut is used
forward of the firewall and in other high temperature areas. In
place of a fiber insert, the threads of a metal locking nut
narrow slightly at one end to provide more friction. An AN363 is
an example of this type of nut. It is capable of withstanding
temperatures to 550-deg. F.

The dash number following
self-locking nut defines the thread size. Self-locking nuts are
very popular and easy to use. They should be used on undrilled
bolts. They may be used on drilled bolts if you check the hole
for burrs that would damage the fiber. One disadvantage,
self-locking nuts should not be used on a bolt that is connecting
a moving part. Am example might be a clevis bolt used in a
control cable application.

Plain Aircraft
Nuts

Plain nuts require a locking
device such as a check nut or lockwasher. They are not widely
used in most aircraft. AN315 is the designation used for a plain
hex nut. These nuts are also manufactured with a right hand
thread and a left hand thread. The check nut used to hold a plain
nut in place is an AN316. If a lockwasher is used a plain washer
must be under the lockwasher to prevent damage to the
surface.

Other Aircraft
Nuts

There are a number of other
aircraft nuts available. Wing nuts (AN350) are commonly used on
battery connections or hose clamps where proper tightness can be
obtained by hand. Anchor nuts are widely used in areas where it
is difficult to access a nut. Tinnerman nuts, instrument mounting
nuts, pal nuts, cap nuts, etc. are all examples of other types
that are used.

Basics of Aircraft
Nut Installation

When using a castle nut, the cotter pin
hole may not line up with the slots on the nut. The
Mechanics General Handbook states "except in cases of
highly stressed engine parts, the nut may be over tightened to
permit lining up the next slot with the cotter pin hole."
Common sense should prevail. Do not over tighten to an extreme,
instead, remove the nut and use a different washer and then try
to line the holes again.

A fiber nut may be reused if you are
unable to tighten by hand.

At least one thread should be projecting
past the fiber on a fiber nut installation.

No self-locking nuts on moving part
installations.

Do not use AN364 or AN365 fiber nuts in
areas of high temperature - above 250' F.

Shear nuts are to be used only in shear
loads (not tension).

Plain nuts require a locking device such
as a lockwasher or a check nut.

When using a lockwasher, place a plain
washer between the surface of the airplane part and the
lockwasher.

Shear nuts and standard nuts have
different torque values.

Use wing nuts only where hand tightness
is adequate.

WASHERS

Finally, a hardware item that is
simple. You are likely to encounter only a couple of different
types of washers AN960 and AN970. The main purposes of a washer
in aircraft installation are to provide a shim when needed, act
as a smooth load bearing surface, and to adjust the position of
castle nuts in relation to the drilled hole in a bolt. Also,
remember that plain washers are used under a lockwasher to
prevent damage to a surface.

AN960 washers are the most
common. They are manufactured in a regular thickness and a
thinner thickness (one half the thickness of regular). The dash
number following the AN960 indicates the size bolt for which they
are used. The system is different from others we have
encountered. As an example, an AN960-616 is used with a 3/8"
bolt. Yet another numbering system. If you see "L" after the dash
number, that means it is a thin or "light" washer. An AN960C
would be - yes, a stainless washer. I can tell you are getting
more familiar with the system so I will throw another wrench into
the equation - an AN970 washer has a totally different dash
number system. I am not even going to tell you what it is. I will
tell you that an AN970 is a larger area flat washer used mainly
for wood applications. The wider surface area protects the
wood.

There are other types of washers.
I mentioned lockwashers that are made several different ways.
They are often split ring, they are sometimes internal tooth and
even external tooth (see Figure 5). You will also find nylon
washers and finishing washers that usually have a countersunk
head. So, as you can see, washers are not quite as confusing as
other hardware even though we can make ft difficult if we
wish.

COTTER PINS AND SAFETY
WIRE

The cotter pins mostly used on
custom aircraft are AN380 and AN381. Cadmium plated cotter pins
are AN380 and stainless are AN381. Cotter pins are used for
safetying bolts, screws, nuts and other pins. You will normally
use them with castle nuts. The MS number you may see is MS24665.
The dash numbers indicate diameter and length of the pin. As an
example, AN380-2-2 would be a cadmium plated pin 1/16" in
diameter and 1/2" long. All supply companies will have charts
showing the various sizes versus the reference number.

Safety wire is also widely used.
The most used sizes in diameter are .020, .032 and .041 or small
variations thereof. The material is usually stainless steel or
brass. The easiest method of installation is acquired by using
safety wire pliers (see Figure 6). The pliers are used to twist
the wire. The wire is installed so that if the nut or bolt begins
to loosen it will increase the tension on the wire. Be sure you
do not overtwist the wire - doing so will weaken the safety wire.
Leave about 36 twists and then cut off the excess wire and bend
its end so you do not snag it with your hand at a later
time.

I want to emphasize the major point of this
article. USE ONLY AIRCRAFT QUALITY
HARDWARE.

Do not assume the engineer role
by using hardware types or sizes that are contrary to your plans
or assembly manual. In future articles I will discuss the other
hardware items including control cable installation, screws,
rivets, turnlock fasteners, etc.

This article was written by Ron
Alexander of Alexander SportAir Workshops.

Ron has been flying since the
age of 16; he flew for the Air Force for five years (including
one year in Vietnam) and started flying for Delta Airlines in
1969, where he now pilots the Boeing 767. He currently owns a J-3
Cub, C-3B Stearman, and a Beech 18. Ron started restoring antique
airplanes in the early 1970's and could not find parts so he
founded the Alexander Aeroplane Company which he operated for 17
years. He sold the company to Aircraft Spruce and Specialty in
1995 so that he could focus his efforts on providing education
within the sport aviation industry.

Ron is currently president of
Alexander SportAir Workshops, a series of "hands-on" workshops on
building airplanes is presented throughout the country for
education. For a schedule of locations and dates of upcoming
workshops and information (prices, curriculum, etc.), call
800-967-5746 or visit their web site at www.sportair.com

This is very sad but I just read in EAA Light Plane World that Mark
Stull died in an accident last November. My condolences to family
and friends for this very tragic loss.

Mark was designing and testing a North Wing weight-shift wing
mounted in a fix-wing like frame, and incorporating a standard
elevator/rudder configuration as a tail.

I have no idea how he was attempting to manage roll control as the
weight-shift flexwing would be difficult to impossible to roll
using just a rudder ... and I'm not aware there were any aileron
type surfaces used or any weight shifting provisions in the
carriage. Even pitch control is quite compromised in that
configuration.

It's very sad story and for what I have read Mark was an
accomplished pilot and quite susccessful designing and flying odd
fix wing designs ... is sad to see that a weight-shift flexwing
ultimately got to him. A wing that by design and controled per
design is extremely safe and easy to control - in my oppinion. But
then again Mark wasn't about "the standard" he liked to try
non-standard. But I hardly see it possible or stable in the way
Mark was trying to accomodate the controls for the weight-shift
flex.

You can read more about in the EAA Light Sport Plane interent
article:
http://www.eaa.org/lightplaneworld/articles/1112_stull.asp

There are also some interesting discussions in the yahoo groups
homebuiltairplanes.com where Mark was a very prolific and welcomed
member.
http://www.homebuiltairplanes.com/forums/light-stuff-area/11442-mark-stull-2.html

This can be a dynamic topic, but there are certainly some markers
to look for in finding yourself a good mechanic that you can
really trust to keep you in the air, safe and happy. You probably
already have a mechanic, but the important thing is in
recognizing if he has more than just the basic skills, but that
certain something that gives you the confidence to trust life and
limb to him. Let’s examine what the traits are that define “a
good mechanic” and steps you can take to find one.

Let’s talk about looking for a good mechanic first. As
in any profession, you’ll find varied degrees of competency.
Just as in choosing a surgeon, you’ll want to avoid marginal
competency and shoot for the elite, or as close to it as
possible. Here are a few questions in the determination if
whether a prospective mechanic is right for you.

(In the interest of simplification and unencumbered continuity
of thought, we will use the pronoun “he” as being asexual.)

Does he come recommended by other aircraft owners?

Do you hear from others that he does a satisfactory job?

Does he have experience in your type aircraft and is he
qualified to work on your Rotax engine with the proper iRMT
ratings?

Do you hear the prospects name brought up favorably in
conversations?

When you talk to the prospect, is he friendly, helpful and
patient before the subject of fees is discussed?

Is your prospect familiar with the tips, tricks and
technical procedures for your Rotax Engine as shown on the
Rotax
Owner Videos.

How many aircraft like yours has he worked on or inspected?

Does he keep you abreast of issues he found and answer your
questions knowledgably?

What’s his philosophy regarding regular and preventive
maintenance?

Is he a self absorbed mechanic, or open-minded to your
ideas, suggestions, concerns and will he research problems
including Rotax Owner videos and
forum?

Does he use an inspection check list, discrepancy list and
do accurate, detailed logbook label entries? (Possibly ask to
see a couple of his labels and check lists)

Does he document well? It’s for your benefit as well as his
legal protection.

Does he give you copies of the maintenance check list, or
other documents for your personal file? This should be an
absolute in case you need it for the FAA, insurance and the
re-sale of your plane. You’re paying for the work, get it the
way you want it not him.

Does he seem to have the proper tools and education for
your particular plane?

Last, but not least and this item is not a real marker of
the mechanic’s professionalism, but should be kept in the back
of your mind. What is the charge? If the price sounds too good
to be true then there may be a reason for it and you might get
exactly what you paid for. Caveat emptor. Now I know this is
not necessarily always true that’s why this is last
consideration while looking for a mechanic that you have
compatibility with and do the job that you expect and deserve.

Your life might be in the hands of the mechanic.
Strive for one who displays all or most of the attributes shown
above.

The mechanic’s motto should be: If there is a problem
with your aircraft, major or minor, I’m going to find it. Your
safety is priority one.
Due to a plane’s wear and tear, loosening of attachment items or
just sitting for extended periods things change and it’s your
mechanics job to find these. He needs to be a skilled hunter
of problems and an organized repairman for these items.

You’re probably already use or have used, a mechanic. Use
these questions, and your own, to determine if he is right for
you. If there are some areas about which you wish your mechanic
would do better then sit down with him and explain your issues
and concerns. You’re the boss. The right mechanic needs to live
up to your expectations.

Life is full of choices. We chose doctors, lawyers expecting them
to be honest; to work in our best interests; to be receptive to
our needs. You fully expect understanding and consideration of
your input. Chose your mechanic in the same way.

AeroConversions AeroInjector I was searching EAA for Rally
information / rules and saw an add for this. It's not exactly a
fuel injector, but similar. Now all we need is a Guinea pig to test
some for us:
http://www.aeroconversions.com/products/aerocarb/index.html $395.00
(I would guess that your would need two for a rotax 912)
AeroInjector 32 shown above with flange mount and optional Intake
Flange Adapter Simplicity in form and function! Utilizing what
hydraulic and pneumatic engineers call the "perfect flow passage"
the AeroInjector (formerly known as AeroCarb) achieves outstanding
performance versatility! AeroInjector body parts are precision
machined from solid 6061 aluminum billets. There are only two
moving parts... no float bowls or secondary jets to complicate
things. A fine adjustment metering needle provides clean burning,
smooth running, outstanding response, and fuel economy. Spigot or
flange mounts easily adapt to popular aircraft and auto conversion
engines. AeroInjector's intake design accepts air filters or carb
heat ducts. The AeroInjector is included as standard with all
AeroVee engines, and is highly recommended to replace the Bing carb
that ships with Jabiru engines. To read about AeroInjector
performance and fuel economy with the Jabiru 3300 engine, read "The
$35 Hamburger" by Sonex's own Kerry Fores, or check-out our
AeroInjector FAQ's. See Fuel Burn and Econom FAQ:
http://www.aeroconversions.com/products/aerocarb/aerocarbfaq.html
What do think? Got an E-LSA and wanna try it? They estimate it will
pay for itself in 100 hrs (200 hrs for two) ;)

In looking at all monthly indexes for the accidents in 2011, very
few accidents seemed to point to trikes. In the non-fatal
accidents, pilot error (mostly judgement) was the main cause in
ones with non-minor injuries. Pilots having these non-fatal
accidents with injuries were either student pilots flying outside
of their CFI's authorized airport or non-certificated flyer, flying
with a passenger illegally.

Two of the troubling fatal accidents seem to come from Kauai, HI
this year with two in mainland.

The mainland fatal accidents were to unrated (in category) pilots
and one was in unregistered trike that was seemingly
being flown under Part 103 though Saber trike would not qualify
under Part 103 criteria and was originally a 2 seater when sold.
The mainland accidents once again show that casual attitude towards
training and not taking enough training or not following rules and
regs and not waiting for your CFI to tell you when you should solo
results in expensive accidents, serious injury or even death. We
have seen this over and over but yet newer trike participants
repeat the story without fail every year.

For accidents to S-LSA trikes and rated CFI's in Hawaii; although
final reports are not out on them, they will most likely point
mainly to operational issues and judgement lapses or according
to some - possible sabotage-.

The mainland seem to have had no fatal accidents for trikes this
year for rated in category pilots flying registered trikes.

Comments: The above accident pilot was being trained at our
facility in Zephyrhills. He was with Army core of engineers and a
private airplane pilot and flew ultralight airplanes on private
airstrip. The instructor was not even made aware that he had gone
out and purchased a used 503 Aquilla trike, nor he had practiced
any landings yet in 5 to 6 hours of dual and was definitely not
ready to fly solo. His wife thought he was just going to do high
speed taxi practice which is a dangerous thing to do for a student.
The trike was damaged substantially on left side consistent with a
stall

4-strokes

With 4-stroke engine, we basically have to answer two major
questions:

Air-cooled vs water-cooled?

Aero-engine or Auto-conversion (or Industrial engine)?

Air-cooled vs water-cooledIt all boils
down to (excuse the pun – I couldn’t resist it) what is
available. The Spitfires (etc) during the war were all
water-cooled – but since then, it seems that the only
water-cooled engines available today are
auto-conversions. Aero engines almost exclusively rely
on air cooling.

And the reasons for this are simply that air-cooled engines
are lighter (no radiator) and simpler (no plumbing).
Water-cooled engines can have closer engineering tolerances,
however, and are immune to such things as shock cooling.

Keeping a water-cooled engine cool
Simply having a radiator is insufficient. Air has to be
able to pass through the radiator fins. And you’d be
surprised at just how many builders seem to completely ignore
this simple fact. I’ve seen radiators shoved up hard
against the firewall, with no POSSIBLE way air could pass out
the back. Placing the radiator out in the free stream
of air is also not the solution. Apart from extremely
high drag, the fact is that air does not easily pass through
radiator fins, and actually finds it easier to veer off to
the sides and go round it.

So we need to place the radiator in such a place where it is
out of the free stream of air (to reduce drag as much as
possible), to slow the air down as much as possible (so that
it can absorb the maximum amount of heat before escaping out
the back) and finally, ensure that there is a good
low-pressure at the rear (to suck the air through).
Here’s a schematic of the water-cooled Razorback F1

Keeping an air-cooled engine cool
Essentially, air passes through a system not because it is
forced in (close the exit and you can force in as much air as
you want – it won’t go in), but because it is sucked
through. Even a small opening – so long as there is a
good suction at the exit – will allow in as much air as you
need. So what we have to identify is where the areas of
high pressure are (the air wants to get IN) and where the LOW
pressure areas are (ie a relative vacuum).

The pressure distribution on the cowl of an aircraft is a bit
unexpected to be honest. It looks like this…

Pressure distribution round cowling

Notice the arrow? Arrows radiating OUTWARDS (eg: top of
the cowl behind the spinner, top of the windshield, bottom
rear of the cowl) indicate areas of relative LOW pressure –
ie a suction. The only two areas where air is trying to
get IN are on the bottom of the cowl, and at the bottom of
the windshield.

And so here’s the surprising thing. By far the greatest
suction is on top of the cowl just behind the spinner.
And it is HERE that we need to vent the warm air.

So if the Razorback were to have an air-cooled engine (eg the
VW), here’s the best way to keep it cool:

Updraft cooling

Bottom line – if you opt for an auto-conversion, you are into
radiators and if you choose an aero-engine (or industrial)
you are wedded to air cooling. So it’s really not that
hard to decide. So the REAL question is really….

Aero vs auto vs industrial

Purpose-built AERO engines:These
come in two flavours. Pre-war designs and modern
engines. I wouldn’t drive a car with an engine
designed before the war, and neither will I fly a plane
equipped with one of these engines. Those in favour
of these dinosaurs go on about how they have stood the test
of time, how they are tried and true etc. But I’m not
convinced. I wouldn’t put one in my car. Bottom
line. What engines am I talking about here?
Your Lycomings and Continentals. Besides, they cost a
FORTUNE. (Did you see the upper case letters in
“fortune”?). Like $28k So, let’s not hear
anything more about them.Fortunately, there are some
excellent MODERN aero engines on the market today (also big
bucks, but not horrendously so). HKS:http://www.hks-power.co.jp/hks_aviation/
In all my searching of the Internet, I have NEVER come
across a single bad word about these engines. Except,
possibly their price (about $12k). They come in
normally aspirated (60hp, 121lbs complete with gearbox and
exhaust) and the new turbo version, which costs
considerably more, and doesn’t produce that much more
power. Rotax:
http://www.rotax-aircraft-engines.com/a_engine_912.htm
Mmmm despite their much-vaunted reliability, I just don’t
LIKE them. They sound terrible (like little sewing
machines whirring away), they are far too fiddly for my
liking, and they cost almost as much as the
Lycomings/Continentals of this world. I think there
are better engines than the 912 (80hp) and the 914 (100hp
turbo). About four times the cost of some other aero
engines, like the VW conversions).Thunder Aero
Engines:http://thunderaviationengines.com/id1.html
These little 4-stroke engines (850cc) offer outstanding
value. A true aero engine at a fraction of the price
you’d expect. And they are fuel injected and
water-cooled, to boot. The engine comes fully ready
(ie exhaust, radiator, gearbox, starter etc) to bolt onto
your airframe, add some gas, strap on a propeller and go
flying.

After an exhaustive search of everything from tiny
industrial engines to large, powerful (120hp)
auto-conversions, I have decided that this is the engine
of choice for the little Razorback. It is a perfect
match for the airframe.

Water-cooled, 121lbs, 80hp. In-line twin only 9
inches wide. In fact, you can thank the distinctive
bump at the top of the Razorback cowl on this engine,
which is much higher than it is wide. I think this
is the engine smaller aircraft have been waiting
for. Certainly I have…

Jabiru:http://www.jabiru.net.au/
This Australian designed and built engine comes in 4
cylinder (85hp, 132lbs) and 6-cylinder (120hp, 178lbs)
and is one of the engines of choice for the Sonex.
I’d take the 4-pot Jabiru over the Rotax any day of the
week. But they are also not cheap. (About twice the
price of some other nice engines).

Smaller AUTO conversions (under
80hp)
If you’re looking at smaller engines, there is only (in our
opinion) one engine to consider: the Geo/Suzuki G10

Larger auto conversions (80 to
100hp)
I know I’m going to be shot down in flames for this, but
although there are literally scores of companies offering
auto conversions of every description, from every
manufacturer imaginable, for me it boils down to a single
engine type – the tried and tested VW. And there are
only three places to get your VW conversion – again, my
personal opinion. The first is Aerovee (a subsidiary
of Sonex Aircraft), the second is Revmaster, and the third
is Great Plains Aircraft.
Aerovee:http://www.aeroconversions.com/products/aerovee/index.html

AeroVee_2.1

This is a lovely engine, and in our opinion, the best on
the market today for the home builder – bar none.
80hp, 161lbs. You buy it in parts, and assemble it
yourself, working from an assembly manual, and a
video. Even I can do it.

Aerovee also offer all sorts of add-on goodies, like
throttle quadrants, optional Nikasil Cylinder upgrade
(saves 10lbs) and there is an active online support group
at Yahoo Groups. One of these will set you back
about $6,500 (USD)

Great Plains:http://www.greatplainsas.com/
Theyoffer three variants, so you get to choose between
front drive, reduction drive and flywheel drive
versions. Prices, power and reputation about the
same as Aerovee. Only hassle is you can’t just buy
an engine, You have to work your way through their
options and “build-up” your engine bits from all their
options. I found it quite confusing. Theyoffer
three variants, so you get to choose between front drive,
reduction drive and flywheel drive versions.
Cost? About the same as the Aerovee.

Revmaster:http://www.revmasteraviation.com/
Not QUITE as pretty as the AeroVee, but this is a very
sweet engine. There is almost nothing of the
original VW engine left in this built-from-the-ground-up
aero engine. Special crank, extra bearing at the
prop hub, custom pistons, conrods, compression chamber
etc etc. AND you can use any prop you like,
including composite or even metal props. The more I
think about it, the more I like this engine. 85hp
take-off power, 80hp continuous. 170lbs.
Cost: about $7,000 (USD)

BMWAnd a very fond
word reserved for the BMW motorcycle
conversions…
Both the R1150 and R1200 series horisontally opposed
engines are frequently used in aircraft. Mainly
because you just can’t break them. They have
dollops of torque, gobs of HP and they will run forever.

The K-series engines are also great little
powerplants. The K-75 (750cc) weighs in at 185lbs
fully oiled, and fitted with a Rotax gearbox. It
produces 73hp, and is just about bullet-proof.
Great engines to turbo, since they will take 8lbs of
boost without blinking an eyelid, and suddenly you have a
reliable turbo aero engine, capable of cruising at its
full 110hp all the way up to 10k feet. One of the
problems with these motors is that they can’t be bought
off the shelf. These are all one-offs, and you need
to know what you’re doing. This is not an option if
you want an easy solution.

INDUSTRIAL engines
Now this is where it gets REALLY interesting. If you
don’t need a lot of power (ie under 40hp) then one of these
might just do the trick. The idea is relatively new,
but there are already two companies which specialise in
aero-converting these little workhorses. (Valley Engineering (US-based)
and
Soloflight (in the UK).

The 50cc Briggs and Stratton engine forms the basis of
this conversion. 30kg, 40hp, 5 litres per hour cruise.
Very tidy.

Soloflight Briggs aero conversion – side view

Valley Engineering use the Generac 40hp
engine in their conversion, which tips the scales at
112lbs (the included 8lb redrive brings the weight to
120lbs. All for $4995 (USD) which includes a custom
made prop, AND the PSRU. Nice. Very nice.

And the latest development is that they now have a newly
ground cam, together with high compression pistons
enabling the engine to produce 50hp. This costs an
extra $750 – but I think this is a bargain.

One of the nice things about the B&S or the Generac
industrial engines is that these motors are designed to
run flat out all day, taking terrible punishment.
They are simple, rugged and while not the most powerful
engines for their size, make up for it with almost
unrivalled reliability. And low cost, of
course. You can buy a brand new engine for about
$1,500 (USD). An engine with redrive, and other
mods to make it suitable for aircraft use will cost you
more (about $5,000) from either Valley or
SoloFlight. But then it is a bolt-on-and-fly
affair, and both of them produce lovely looking
conversions.

And it only drinks about 6 litres an hour. That is
under $7.50 for an hour’s flying. Very impressive.

A new purpose-built aero engine from
Verner
If you’re looking for something in the region of 40hp, then
you have just GOT to check out the new Verner JCV-360.
It is a purpose-built aero engine, 4-stroke, water cooled
boxer. Weight = 26kg. Wow! Talk about a
great pedigree. At 35hp, however, it just doesn’t quite
have the oomph I’m personally looking for, but if you can
live with 35hp, then this one might be for you.
Cost? Apparently (I have this 3rd hand, however…
2,600 Euro)